On 19 March, 2009 - Harry Putnam sent me these 1,4K bytes:
I'm finally getting close to the setup I wanted, after quite a bit of
experimentation and bugging these lists endlessly.
So first, thanks for your tolerance and patience.
My setup consists of 4 disks. One holds the OS (rpool) and 3 more all
the same model and brand, all 500gb.
I've created a zpool in raidz1 configuration with:
zpool create zbk raidz1 c3d0 c4d0 c4d1
No errors showed up and zpool status shows no problems with those
scrub: none requested
NAME STATE READ WRITE CKSUM
zbk ONLINE 0 0 0
raidz1 ONLINE 0 0 0
c3d0 ONLINE 0 0 0
c4d0 ONLINE 0 0 0
c4d1 ONLINE 0 0 0
However, I appear to have lost an awfull lot of space... even above
what I expercted.
zbk 913G 26K 913G 1% /zbk
It appears something like 1 entire disk is gobbled up by raidz1.
The same disks configured in zpool with no raidz1 shows 1.4tb with df.
I was under the impression raidz1 would take something like 20%.. but
this is more like 33.33%.
So, is this to be expected or is something wrong here?
Not a percentage at all.. raidz1 "takes" 1 disk. raidz2 takes 2 disks.
This is to be able to handle 1 vs 2 any-disk failures.
Then there's the 1000 vs 1024 factor as well. Your HD manufacturer says
500GB, the rest of the computer industry says ~465..